Amazon calculates a product's star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers and factors that establish reviewer trustworthiness.
This is a very nice book by Deepak Gupta. Book contains different inspirational quotes, which are very useful yo motivate ourself very well. Collection of quoets is very nice. Author did very nice work. I like most of the quoets. Must be read.